Credits
This website is built using open resources, including fonts, word lists, the data behind word order, the topic word banks, and the picture symbols shown beside words. Thank you to the researchers and projects that made these freely available.
Vocabulary
The words in the word bank come from three published word lists, each adding words the others don't.
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New General Service List (NGSL) 1.2 — a
research-based list of about 2,800 of the most useful high-frequency
words for learners of English.
Browne, C., Culligan, B., & Phillips, J. — newgeneralservicelist.com · License: CC BY-SA 4.0 -
New Dolch List (NDL) 1.1 — an updated take on
Edward Dolch's classic list of everyday sight words, adding the words
the NGSL doesn't cover.
Source: newgeneralservicelist.com · License: CC BY-SA 4.0 -
CEFR-J Wordlist (ver 1.5) — a list of about
3,900 words sorted by CEFR level for learners of English, compiled by
Yukio Tono, Tokyo University of Foreign Studies; retrieved via the
Open Language Profiles mirror.
Source: cefr-j.org via github.com/openlanguageprofiles/olp-en-cefrj · License: free for research and commercial use with citation; copyright Tono Laboratory, TUFS.
The three lists were combined, expanded to include common inflected forms (plurals, verb tenses, comparatives), and tagged with each word's part of speech, then reviewed, edited and added to by hand for the students this app is built for. Per the CC BY-SA 4.0 license, this adapted word list is itself distributed under CC BY-SA 4.0.
Word order
These norms decide which words appear first in the word bank, and which words each Word level (in Settings) includes.
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SUBTLEX-US — how often each word appears in
American movie and TV subtitles, one input to the score that
orders the word bank.
Brysbaert, M., & New, B. (2009). Moving beyond Kučera and Francis: A critical evaluation of current word frequency norms and the introduction of a new and improved word frequency measure for American English. Behavior Research Methods, 41, 977–990.
ugent.be/pp/experimentele-psychologie · License: CC BY-NC-SA 4.0 -
Age-of-acquisition norms — the age at which
children learn to write each word, the other input to the score
that orders the word bank.
Green, C., Kong, A. P.-H., Brysbaert, M., & Keogh, K. (2025). Crowdsourced and AI-generated age-of-acquisition (AoA) norms for vocabulary in print: Extending the Kuperman et al. (2012) norms. Behavior Research Methods. Built on Kuperman, V., Stadthagen-Gonzalez, H., & Brysbaert, M. (2012). Age-of-acquisition ratings for 30,000 English words. Behavior Research Methods, 44, 978–990.
osf.io/ch48r · License: CC BY 4.0 -
Concreteness ratings — how easy each word is
to picture (1 = abstract, 5 = concrete), one input to the Word level
setting. A concrete word such as “mosque” is placed a
level earlier than an abstract word of the same age.
Brysbaert, M., Warriner, A. B., & Kuperman, V. (2014). Concreteness ratings for 40 thousand generally known English word lemmas. Behavior Research Methods, 46, 904–911.
doi.org/10.3758/s13428-013-0403-5
Topic word banks
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USDA FoodData Central — the Foods & Plants word bank
starts from the food names and product categories in this database
(April 2026 download).
U.S. Department of Agriculture, Agricultural Research Service. FoodData Central. fdc.nal.usda.gov · License: public domain (CC0 1.0) -
English WordNet 2025 — the Animals word bank
is built from its animal vocabulary, and it also helped sort
candidate words for the Sports and Foods & Plants word banks. English WordNet continues
Princeton University's WordNet.
en-word.net · License: CC BY 4.0 -
Wikidata — the Sports word bank adds the
names of modern and regional sports from Wikidata's list of sports.
wikidata.org · License: public domain (CC0 1.0) -
wordfreq — the usage-frequency numbers for
Sports and Foods & Plants words that aren't in the core word list. wordfreq combines
several sources, including Wikipedia, movie and TV subtitle
collections (OpenSubtitles, SUBTLEX), Google Books, and web text.
Speer, R. (2022). rspeer/wordfreq: v3.0 (v3.0.2). Zenodo. doi.org/10.5281/zenodo.7199437 · License: code Apache-2.0; data CC BY-SA 4.0 -
CMU LOGIOS Lexicon Tool — estimated
pronunciations for topic words that the CMU Pronouncing Dictionary
(see below) doesn't list, used to generate creative-spelling matches
the same way as for the core list. These are automatic
letter-to-sound guesses, not dictionary entries.
Carnegie Mellon University · speech.cs.cmu.edu/tools/lextool.html
Because the frequency values come from CC BY-SA data, the Sports and Foods & Plants word banks are themselves distributed under CC BY-SA 4.0, like the core word list.
The scores that combine those two sources
(data/frequency.json) are distributed under
CC BY-NC-SA 4.0.
Pronunciation data
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CMU Pronouncing Dictionary (cmudict-0.7a) —
real pronunciations for each word, used to generate a handful of
plausible creative spellings a beginning speller might type, as one
of the ways this app recognizes an in-progress word from an early
or phonetic spelling.
Copyright © 1993–2008 Carnegie Mellon University.
speech.cs.cmu.edu/cgi-bin/cmudict · License: BSD-style, reproduced in full below as its terms require.
CMU Pronouncing Dictionary license text
Copyright (C) 1993-2008 Carnegie Mellon University. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. The contents of this file are deemed to be source code. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. This work was supported in part by funding from the Defense Advanced Research Projects Agency, the Office of Naval Research and the National Science Foundation of the United States of America, and by member companies of the Carnegie Mellon Sphinx Speech Consortium. We acknowledge the contributions of many volunteers to the expansion and improvement of this dictionary. THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY “AS IS” AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Picture symbols
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ARASAAC pictograms — the small pictures shown
beside many words. Each picture was chosen by hand for its word.
Pictogram author: Sergio Palao · Origin: ARASAAC (arasaac.org) · Owner: Government of Aragón (Spain) · License: CC BY-NC-SA 4.0
Ready Words is free and non-commercial. The pictures on this site have been adapted — resized, and some converted to black and white — and, per the license, the adapted pictures are shared under the same CC BY-NC-SA 4.0 license.
Typography
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Lexend — open-source typeface designed and
researched around reading proficiency.
Source: Google Fonts (original at lexend.com) · License: SIL Open Font License 1.1
Bundled locally asfonts/Lexend-Variable.woff2(Latin subset) for offline/no-network use.